Report says U.S. should adopt tougher standards to halt invasive species

MUSKEGON -- The United States should immediately adopt international ballast water treatment standards to keep ocean freighters from hauling more foreign species into the Great Lakes, according to a National Research Council report.

Transoceanic freighters have imported 57 foreign species since 1959, when the St. Lawrence Seaway opened the Great Lakes to global shipping. There are 185 invasive species in the lakes, according to federal data.

Several of the most harmful of the most harmful invaders -- including zebra mussels, quagga mussels and round gobies -- snuck into the lakes in ocean freighters' ballast water tanks, according to government data.